Midlife in the United States (MIDUS) Series

The Midlife in the United States (MIDUS) Series is a data collection stemming from the work of the John D. and Catherine T. MacArthur Foundation Research Network on Successful Midlife Development (MIDMAC). MIDMAC is an interdisciplinary research group consisting of numerous scholars from a wide range of disciplines and backgrounds. It was established in 1989 to study a period in the lifespan -- middle age. The primary objective of MIDMAC is to identify the major biomedical, psychological, and social factors that permit some people to achieve good health, psychological well-being, and social responsibility during their adult years. To do this, MIDMAC collected a series of data to establish an empirical basis for documenting what happens in the middle years and to identify the factors that determine the course of midlife development.

The first wave of data collection (MIDUS I) began in 1995 with a National Survey of Midlife Development in the United States. The main data collection consisted of a general population survey, as well as surveys of siblings of the general population respondents, and a twin pairs sample. The main data collection also included an oversample of five metropolitan areas. In addition to the main national survey, random subsamples of respondents were recruited to participate in in-depth investigations of selected topics, such as management strategies for coping with stressful experiences, a national study of daily experiences, and a study of psychological experiences.

In 2002 the University of Wisconsin Institute on Aging was awarded a grant from the National Institute on Aging to continue the MIDUS series.

MIDUS datasets can be linked via the M2ID variable.

Additionally, the MIDUS series includes the Midlife in Japan (MIDJA) studies.
In 2008, with funding from the National Institute on Aging (NIA), the MIDJA studies began with a baseline sample of Japanese adults (N = 1,027) aged 30 to 79 from the Tokyo metropolitan area. These baseline survey data were collected on sociodemographic characteristics (age, gender, marital status, educational status), psychosocial characteristics (e.g., independence/interdependence, personality traits, sense of control, goal orientations, social support, family obligation, social responsibility), mental health (depression, anxiety, well-being, life satisfaction), and physical health (chronic conditions, health symptoms, functional limitations, health behaviors); biomarker data were later collected from a subset of the baseline cases. The survey and biomarker measures obtained in MIDJA parallel those in the MIDUS 1 and 2 samples - The central objective was to compare the Japanese sample (MIDJA) with the United States sample (MIDUS) to test hypotheses about the role of psychosocial factors in the health (broadly defined) of mid- and later-life adults in Japan and the U.S.

Users should review the "Guide to Merging the MIDJA and MIDUS Data" (in the available downloads for the MIDJA studies) for more information.

In 2011-2014, the MIDUS Refresher study recruited a national probability sample of 3,577 adults, aged 25 to 74, designed to replenish the original MIDUS 1 baseline cohort and paralleling the five decadal age groups of the MIDUS 1 baseline survey. The MIDUS Refresher survey employed the same comprehensive assessments as those assembled on the existing MIDUS sample, but with additional questions about the effect of the economic recession of 2008-09. This new cross-sectional MIDUS sample allows the examination of period effects on health (mental and physical) related to the economic recession by comparing the pre-recession MIDUS 1 sample with the post-recession MIDUS Refresher sample.